Current grey water treatment systems are inefficient and do not produce much treated water that can be reused. For example, grey water produced in a house or in a large common carrier vehicle such as a plane, train, ship, or bus contains different levels of contamination. The grey water that is produced while water is running in a sink may be uncontaminated while the grey water that is produced from washing dishes may be highly contaminated.
However, current grey water treatment systems generally mix all of the grey water together regardless of its source or how contaminated it might be prior to treatment. The current grey water treatment systems must then treat all the grey water according to the treatment needs of the most contaminated grey water. This reduces the efficiency of the current grey water treatment systems and also increases the use of treatment reagents, which may be environmentally harmful.